Celts held the festival of the Irish god Lugh and later, the Anglo-Saxons marked the festival of hlaefmass – loaf mass or Lammas.
Wikipedia says: Lughnasadh or Lammas is also the name used for one of the eight sabbats in the Wiccan Wheel of the Year. It is the first of the three autumn harvest festivals, the other two being the Autumn equinox (also called Mabon by Wiccans) and Samhain. It is seen as one of the two most auspicious times for handfasting, the other being at Beltane.
Some Wiccans mark the holiday by baking a figure of the “corn god” in bread, and then symbolically sacrificing and eating it.